Primary hyperparathyroidism as the leading symptom in a patient with a Y791F RET mutation.

Division of Endocrinology and Metabolism, Department for Internal Medicine III, Medical University of Vienna, Austria.
Thyroid (Impact Factor: 3.84). 11/2005; 15(11):1303-8. DOI: 10.1089/thy.2005.15.1303
Source: PubMed

ABSTRACT Primary hyperparathyroidism (PHP; serum calcium 2.75 mmol/L, PTH 226 pg/ml) had been the first clinical manifestation of MEN-2A in a female patient (aged 55 years) with a mutation (Y791F, TAT-->TTT) in exon 13 of the RET proto-oncogene. The patient has a pentagastrin-induced rise in serum calcitonin (up to 57 pg/ml) considered normal for noncarriers but abnormal in family members of MEN-2 patients. This is the first case of MEN-2 due to this specific mutation with primary hyperparathyroidism as the first manifestation of the disease. In addition, the patient harbored, within the Menin gene, a polymorphism (D418D) reportedly associated with sporadic primary hyperparathyroidism. This case report indicates that molecular biological tests in MEN- 2 may only suggest a certain phenotype but cannot predict it with certainty. It may also suggest that genetic screening for MEN-2 may be advisable in patients with primary hyperparathyroidism and a borderline-high pentagastrin stimulation test, even in the absence of a positive family history.

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